Making Plastic Bottles from Sugarcane and Captured CO₂
A new study from the labs of Durham University’s Dr. Andrew Smallbone lays out a pathway to making plastic bottles from organic waste material and CO2 captured from power plants. A thorough analysis of the economics shows this process could even be cost competitive for making things like plastic bottles.
The process could start with something like the leftover plant material from sugarcane pressing. After a few reaction steps, which include the addition of some captured CO2 and some ethylene glycol produced from corn plants, you’d end up with a plastic polymer called polyethylene furandicarboxylate—otherwise known as PEF. Functionally, it’s similar to the PET plastic used for water and soda bottles, denoted by the number 1 recycling symbol.
Every step in the process has been at least demonstrated before, and some are quite common, so the paper doesn’t spend much space on the chemistry. Instead, the researchers engage in life cycle analysis of the manufacturing process to estimate exactly how this method of making PEF would stack up with the competition.
Interestingly, other proposed methods for making PEF are actually associated with lower emissions than that. However, those methods rely on using food sugars rather than leftover plant material—something the researchers wanted to avoid.
There is one additional consideration: it might well be that you could make a PEF bottle with 25% less plastic. While PEF and PET have similar enough properties that they fit the same niche, PEF is a little sturdier. “As such, the PEF production cost per bottle could be the same as or lower than that of PET,” the researchers write.
This work represents an innovative way to repurpose waste materials using known processes to come closer to achieving a renewable-based alternative to a fossil-based incumbent.
Read PEF Plastic Synthesized from Industrial Carbon Dioxide and Biowaste at nature.com